The device and the method are preferably used in histology. Histology deals with the examination of tissue samples from patients. The most common procedure is that the tissue samples are taken from the patients, embedded in paraffin, thin sections are cut with the aid of a microtome from the specimen blocks produced in this way, and one thin section each is placed on one carrier each. Subsequently, in a further process the specimens are treated, in particular dyed, before they are supplied to a microscope for diagnostic evaluation.
During the treatment, the carriers on which the specimens are placed are immersed with the aid of a transport container and a transport mechanism in a reagent container filled with reagent, and are left therein for a predetermined time before they are taken out of the reagent container and are transported with the aid of the transport mechanism into another reagent container. The control of this treatment process is preferably effected computer-controlled. It is important that the reagent containers are each filled with the correct amount of reagents. When the reagent container is filled with too much reagent, then it may happen that the reagent spills over the reagent container owing to the displacement of the reagent by the transport container and the carriers. The result is that the device for treating the specimens and/or the surrounding area is contaminated. It is particularly critical when other reagent containers are contaminated by the reagent spilled over a too full reagent container. This is particularly the case given devices in which the reagent containers are arranged above one another in several planes. In order to prevent such a contamination of one reagent container by the reagent of another reagent container, reagent containers having a defined mechanical overflow are used in the prior art, through which overflow the reagent can run off in a controlled manner in case of overfilling, and a contamination of other reagent containers, the device and/or the surrounding area is avoided. What is disadvantageous here is that by means of the mechanical overflow, relief is only given in case of an overfilling of the reagent container. It is, however, likewise critical when a reagent container is not filled with sufficient reagent so that the specimens immersed in the reagent container are not or not completely covered with the reagent so that the desired treatment of the specimens is not guaranteed.